This application claims priority to an application entitled xe2x80x9cPortable Wireless Terminal with Ground Connecting Device Using Hinge Modulexe2x80x9d filed in the Korean Industrial Property Office on Jul. 19, 2002 and assigned serial No. 2002-42566, the contents of which are hereby incorporated by reference.
1. Field of the Invention
The present invention relates to a portable wireless terminal and, more particularly, to a folder type terminal which can reduce an electromagnetic wave absorption rate by using a hinge module and a method for using the same.
2. Description of the Related Art
Typically, a portable wireless terminal is classified into a bar type, flip type and folder type in accordance with its appearance.
The bar type terminal is a type that comprises a single body housing mounted with data inputting and outputting devices and transmitting and receiving modules. In the terminal of this type, a malfunction may occur because the key pad which serves as data inputting and outputting device is always exposed and there are limitations in miniaturization due to the problem in securing a sufficient distance between the transmitting and the receiving modules.
The flip type terminal is a type that comprises a main body, a flip cover and a hinge module which interconnects the main body and the flip. The data inputting and outputting devices and transmitting and receiving modules mounted in the main body, and the flip cover covers the key pad which serves as the data inputting device, to thereby protect and prevent malfunction of the data inputting device. However, the flip type terminal also has limitations in miniaturization due to the problem in securing a sufficient distance between the transmitting and receiving modules.
The folder type terminal is the type that comprises a main body, a folder and a hinge module which rotatably interconnects the main body and the folder, such that the terminal is opened or closed by rotating the folder. In the state where the folder is in close contact with the main body, the terminal is in the communication standby mode and thus malfunction of the keypad can be prevented. In the communication mode, the folder is extended and thus it is possible to secure a sufficient distance between the transmitting module and the receiving module. This feature is also advantageous for miniaturization of the terminal.
FIG. 1 is a perspective view showing a conventional portable wireless terminal, in particular, a folder type terminal 100.
As shown in FIG. 1, the conventional folder type terminal 100 comprises a main body 110 and a folder 150 which are interconnected to be capable of being opened and closed by being rotated by a hinge module (not shown). The main body 100 includes a key pad 113 and a transmitting module 115 on its housing 111, and includes a side hinge arm 117 at each side of its upper end.
The folder 150 includes an exposed display device 153 on its housing 151 and a receiving module 155 at its upper end. The folder housing 151 includes a center hinge arm 157 at its lower end, which is interposed between the side hinge arms 117 of the main body housing 111 and rotatably connects the folder 150 to the main body 10. The center hinge arm 157 includes a certain hinge module.
An example of a hinge module is disclosed in U.S. Pat. No. 6,292,980 granted on Sep. 25, 2001 in the name of the present applicant. The disclosed hinge module comprises a hinge cam and a hinge shaft which are formed with a peak-shaped part and a valley-shaped part, respectively, and a spring which renders the hinge cam and the hinge shaft to come into close contact with each other. The hinge cam, the hinge shaft and the spring are received within a hinge housing, and the folder or flip is opened or closed by using the cooperation between curved surfaces of the peak and valley-shaped parts and the elastic force exerted by the spring.
Meanwhile, research results which show that electromagnetic waves are harmful to human body are being successively reported, and thus many countries in the world are tending to strengthen the regulation for emission of electromagnetic waves from a portable wireless terminal.
However, the methods for reducing the emission of electromagnetic waves from a portable wireless terminal are limited to attaching an electromagnetic wave absorbing material on the antenna or the electric power supply part of the antenna, or moving the electromagnetic wave concentration position or canceling electromagnetic waves by changing a ground pattern formed on the inner side of an injection molded component of the terminal. Moreover, although those methods are effective in reducing electromagnetic wave absorption rate, they tend to deteriorate radiation characteristics of the antenna. Those methods also have a problem in that the position of the electromagnetic wave absorbing material or the ground pattern should be adjusted through repeated tests and inspections in order to satisfy both the electromagnetic wave absorption rate of human body and the radiation characteristics of the antenna.
Accordingly, the embodiments of present invention described herein endeavor to substantially solve the above-mentioned problems occurring in the known devices. Hence, an object of the present invention is to provide a portable wireless terminal which reduces electromagnetic wave absorption rate.
Another object is to provide a portable wireless terminal which can satisfactorily maintain the radiation characteristics of the antenna while reducing the electromagnetic wave absorption rate.
In order to accomplish these and other objects, an embodiment of the present invention provides a portable wireless terminal which includes a main body and a folder which is rotatably connected to the main body. The terminal further comprises a housing of the main body which is coated with an electrically conductive material on the inner surface in order to provide a ground for an electric circuit device mounted in the main body, a housing of the folder which is coated with an electrically conductive material on the inner surface in order to provide a ground for an electric circuit device mounted in the folder, and a hinge module which is received within the folder and rotatably connects the folder to the main body, with the hinge module electrically interconnecting the ground of the main body and the ground of the folder.
An embodiment of the present invention also provides a portable wireless terminal which includes a main body and a folder which is rotatably connected to the main body. The terminal further comprises a main body housing which is provided with a side hinge arm at each side of the upper end, a folder housing which is provided with a center hinge arm at the center of the lower end, with the center hinge arm corresponding to the side hinge arms of the main body, a hinge module which is received within the center hinge arm and rotatably connects the folder to the main body, and a hinge dummy which is fixedly engaged with the side hinge arms of the main body. The hinge dummy is connected to the hinge module, which comprises a hinge housing which has an open end provided with a shaft hole and a closed end, with one side of the hinge housing being opened to form a receiving space and a side wall of the hinge housing being formed with a guide groove of a predetermined length. The hinge module also comprises a hinge shaft which is rotatably received within the hinge housing and which is provided with a peak-shaped part at one end and a hinge stem at the other end, with the hinge stem being projected through the shaft hole formed in the hinge housing and connected to the main body; and a hinge cam which has a valley-shaped part corresponding to the peak-shaped part of the hinge shaft, one side of the hinge cam being provided with a guide projection which performs rectilinear movements within the guide grove formed in the hinge housing. The hinge module further includes an elastic portion which is abutted against the internal wall in the open end side of the hinge housing and presses the valley-shaped part of the hinge cam and the peak-shaped part of the hinge shaft toward each other to come into close contact with each other, and a hinge stopper which is fixedly engaged with the inner wall of the open end side of the hinge housing, with the hinge stopper being provided with a through hole, through which the hinge stem of the hinge shaft is extended, and a stopper which extends from a side of the hinge stopper and longitudinally projected from a side of the open end of the hinge housing. The hinge dummy comprises an engaging hole, into which the hinge stem is fixedly fitted, and b) a guide groove which is formed on the circumferential surface of the hinge dummy and provides a passageway to which the stopper of the hinge stopper is movably connected.